1. Field of the Invention
The present invention relates to an air conditioner using two compressors, and more particularly, to an accumulator in an air conditioner for containing liquid refrigerant so as to permit flow of only gaseous refrigerant to a compressor.
2. Background of the Related Art
In general, the air conditioner controls a room temperature and humidity according to a required condition. As shown in FIG. 1, the air conditioner is provided with a compressor 1 for compressing refrigerant by using a rotating force, an outdoor heat exchanger 7 and an indoor heat exchanger 3 for condensing or evaporating the refrigerant by means of a heat exchange, and an expansion valve 5 for reducing a pressure of the refrigerant. And, there is an accumulator 6 connected to an inlet to the compressor.
In cooling the room by using the air conditioner, the refrigerant undergoes a refrigeration cycle, in which the refrigerant is compressed to a high temperature and pressure, condensed at the outdoor heat exchanger 7 by heat exchange, involved in a pressure drop as the refrigerant passes through the expansion valve 5, evaporated at the indoor heat exchanger 3 by heat exchange with room air, and provided to the compressor, again. The accumulator 6 has a body for storing the refrigerant, an inlet tube on a top of the body, and a U curved outlet tube. As the inlet of the accumulator is connected to an outlet of the indoor heat exchanger, and an outlet of the accumulator is connected to an inlet of the compressor, the refrigerant passed through the indoor heat exchanger flows into the accumulator, and separated into liquid phase refrigerant and a gas phase refrigerant by a difference of density, wherein the liquid phase refrigerant is stored in the body and only the gaseous refrigerant flows to the compressor through the outlet tube.
In the meantime, the aforementioned air conditioner has a poor air conditioning efficiency because the room cooling is carried out at a maximum rate even if no high cooling load is required, because the room air temperature is appropriate. FIG. 2 illustrates an air conditioner having two compressors of different compression capacities provided for solving the foregoing problem, provided with two compressors 1a and 1b of different capacities, for compressing a refrigerant, oil separators 2a and 2b for separating oil leaked from respective compressors, and oil recovery tubes 4a and 4b for recovering the oil separated at the oil separators to the compressor. Each of the oil separators 2a and 2b has flow path controlling means 8 for setting up a flow path to respective heat exchangers, so that the compressed refrigerant flows to the indoor heat exchanger and the outdoor heat exchanger 3 and 7 through the flow path controlling means 8. There is expansion valve 5 fitted between the heat exchangers for dropping a pressure of the refrigerant for an easy phase change of the refrigerant, and two accumulators 6a and 6b arranged to connect the flow path controlling means and the compressors for making only gaseous refrigerant to flow to the compressors among refrigerant flowing toward the compressors.
However, the air conditioner having two compressors is involved in a pressure drop since the high temperature, high pressure refrigerant from the compressors 1a and 1b passes through the oil separators 2a and 2b, which reduces a flow speed of the refrigerant flowing through the heat exchanger, that reduces a heat transfer efficiency. And, the use of the oil separators and the oil recovery tubes 4 cause the following many problems. The leakage of the oil carried on the refrigerant used for lubrication and prevention of overheat of the compressors during operation of the air conditioner causes trouble of the compressors. The additional use of oil separators for recovering the oil circulating through the air conditioner to the compressors increases cost, and makes the structure of the air conditioner complicated. And, many experiments and calculations are required for selecting a length of the oil recovery tubes 4, in general capillary tubes, which connect the compressors and the oil separators. The return of high pressure refrigerant to the compressors again through the oil recovery tubes 4 reduces a refrigerant flow rate circulating through the air conditioning cycle, which reduces the cooling and heating efficiency. Moreover, the easy adsorption of contaminants produced during operation of the air conditioner by the oil, difficulty of removal of the contaminants from the oil, and recovery of the contaminants at the recovery tubes together with the oil, results in blocking of the oil recovery tubes, which impedes recovery of the oil to respective compressors through the oil recovery tubes, to cause trouble on the compressors. Moreover, the provision of the oil separator and the accumulator to each compressor increases a weight of the air conditioner, makes a structure complicated, and pushes up a cost.
Accordingly, the present invention is directed to an accumulator in an air conditioner that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide an accumulator in an air conditioner, in which a pressure drop of a high pressure refrigerant is prevented for improving cooling and heating efficiency.
Another object of the present invention is to provide an accumulator in an air conditioner, which can recover oil required for operation of a compressor to the compressor for prevention of out of order of the compressor, and simplify a system of the air conditioner.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, the accumulator in an air conditioner includes a body having an inlet formed in a top portion thereof, first means fitted near to the inlet in the body for filtering contaminants, second means fitted under the first means for filtering oil, and an outlet tube for recovering oil stored in the body to a compressor.
The first means preferably includes a mesh with many holes for separating contaminants from refrigerant flowing in through the inlet, an edge of which is fixed to an upper portion of the body for separating contaminants from the refrigerant.
The second means preferably includes a screen having a plurality of circumferential pass through holes having an edge fixed to the body under the first means.
The outlet tube has a plurality of tubes each having one end positioned under the screen, the other end projected from the body, and an oil hole at a lower portion thereof.
The number of outlet tubes is the same with a number of compressor provided in a system.
In another aspect of the present invention, there is provided an air conditioner including a compressor for drawing, compressing, and discharging refrigerant to heat exchangers, a flow path controlling means for selecting a refrigerant flow path depending on cooling/heating condition, an outdoor heat exchanger connected between the flow path controlling means and an expansion valve which reduces a pressure of the refrigerant, for making heat exchange between the refrigerant and an external air, an indoor heat exchanger connected between the expansion valve and the flow path controlling means for making heat exchange between the refrigerant from the expansion valve and a room air, to evaporate the refrigerant, and an accumulator for receiving two phased refrigerant from the indoor and outdoor heat exchangers, separating gaseous refrigerant and oil from the two phased refrigerant flow, and letting the gaseous refrigerant and oil be flowed to the compressor.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.